Pain beneath the shoulder blade occurs in the region of the scapula, a triangular bone connected to numerous muscles stabilizing the shoulder and upper back. Due to the complex network of muscles, nerves, and proximity to major organ systems, the source of this discomfort can be varied. This common complaint can range from a minor annoyance to a signal of a more serious health issue.
Common Muscular and Postural Causes
The majority of pain experienced under the shoulder blade originates from the muscles and soft tissues in the upper back, frequently due to poor posture or overuse. The rhomboid muscles, which connect the inner edge of the shoulder blade to the spine, are often the primary source of a deep, aching sensation. Overstretching or straining these muscles during activities like heavy lifting or prolonged computer use can lead to a strain or painful muscle spasm. This discomfort often feels like a tight “knot” and worsens when moving the shoulders or taking a deep breath.
Poor posture, particularly the rounded-shoulder, forward-head position common with long hours of desk work, places chronic strain on the back muscles. This slouching posture overworks muscles like the rhomboids and the middle and lower trapezius, which constantly fight gravity to stabilize the shoulder blades. Over time, this sustained tension leads to myofascial trigger points, which are hyperirritable spots within the muscle tissue. The levator scapulae muscle is another common site for trigger points that refer pain along the inner border of the scapula.
These postural habits create muscle imbalances, where the chest muscles tighten and the upper back muscles weaken, perpetuating the cycle of strain and pain. The constant state of contraction leads to reduced blood flow and the accumulation of metabolic waste products, contributing to the persistent, dull ache. Addressing these mechanical issues, rather than just treating the symptom, is typically the most effective long-term solution for this type of discomfort.
Problems Originating in the Spinal Column
Pain felt under the shoulder blade can also be a manifestation of structural issues in the spine, particularly the cervical (neck) and thoracic (mid-back) regions. A spinal disc issue in the lower cervical spine (C5-C7) can cause pain that radiates, or is referred, laterally to the area near the shoulder blade. This occurs when the inner material of a disc ruptures or bulges, irritating or compressing a nearby nerve root.
Facet joints, the small joints connecting the vertebrae, can become irritated or inflamed due to poor posture or degenerative changes. Pain originating from these thoracic or cervical facet joints is often perceived as a sharp, localized ache directly under the scapula. Unlike a simple muscle strain, nerve root compression often presents with additional symptoms, such as tingling, numbness, or weakness that may travel down the arm.
A misaligned rib, known as a subluxated rib, can cause sharp pain directly under the shoulder blade. This condition occurs when a rib pops out of its joint with the thoracic vertebra, often after a sudden movement or excessive strain. Pain from a spinal source may also feel different from muscular pain, sometimes worsening with specific neck movements or persisting even when the muscles are at rest.
Referred Pain from Other Organs
Although less common, pain under the shoulder blade can be referred pain originating from internal organs. This occurs because the nerves supplying the organs and the upper back share similar pathways, causing the brain to misinterpret the source of the pain. Gallbladder disease, such as gallstones or inflammation, frequently refers pain to the right shoulder blade area. This pain is often constant and unrelated to movement or posture.
Cardiac events, particularly in women, can sometimes present with pain in the upper back and under the left shoulder blade, rather than the classic chest pain. Conditions affecting the lungs, such as pleurisy or a pulmonary embolism, can also manifest as pain in the chest wall or the shoulder blade area. The presentation is often distinct from muscle pain, typically involving other symptoms like shortness of breath, nausea, or sweating.
Essential Next Steps and Red Flags
For most individuals, pain under the shoulder blade resolves with simple self-management strategies, such as applying heat or ice and engaging in gentle stretching. Over-the-counter anti-inflammatory medications can help reduce pain and local inflammation associated with muscle strain. Correcting ergonomic setup, taking frequent breaks from prolonged sitting, and focusing on exercises that strengthen the upper back muscles are practical steps to prevent recurrence.
However, certain “red flag” symptoms necessitate immediate medical evaluation to rule out the more serious causes of referred pain. Seek urgent care if the pain is sudden, severe, or accompanied by chest pressure, difficulty breathing, or excessive sweating. Other concerning signs include pain that does not improve with rest, pain that worsens at night, unexplained weight loss, or persistent numbness and tingling in the arms. These symptoms suggest a potential issue beyond simple muscular tension that requires professional diagnosis.